Facebook authentication in iOS

Facebook authentication is an already present topic, but within the scope of this recipe, we're going to cover how we can add the Firebase side by side with the Facebook authentication logic.

Getting ready

Before we actually start implementing the functionalities, please go and edit your Podfile and paste in the following entry:

       pod 'FBSDKCoreKit'
       pod 'FBSDKLoginKit'
       pod 'Firebase/Auth'

Now save, and then in your favorite terminal of choice, type the following command:

    ~> pod install

This command will download the needed dependency and its dependencies, and configure your project accordingly. After that, in your project finder,...